Telephone-alarm



(No Model.)

J. F. KETTELL.

TELEPHONE ALARM.

JV?! Patented Apr.25, 1882.

N. FErERs mo-Lilm nphur, Waih'm ggggg C.

.. UNITE STATES PATENT OFFICE.

JAMES F. KETTELL, OF WORCESTER, MASSACHUSETTS.

TELEPHONE-ALARM.

SPECIFICATION forming part of Letters Patent No. 257,019, dated April 25, 1882,

Application filed September 3, 1881. (No model.)

To all whom it may concern:

Be it known that I, JAMES F. KETTELL, a citizen of the United States, residing at Worcester, in the county of Worcester and State of Massachusetts, haveinvented certain new and useful Improvements in Telephone-Alarms; and I do hereby declare the following to be a full, clear,-and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same, reference being bad to the accompanying drawings, and to the letters orfigures of reference marked thereon, which form a part of this specification.

This invention relates to that class of telephone-alarms commonly known as individual calls, the object of which is to enable the central or main oifice of a telephone system to ring the alarm of one subscriber or station without ringing those of the others on the same circuit.

My present improvement consists in the following construction and arrangement, which will hereinafter be fully described, and the points of novelty set forth in the claims.

Referring to the accompanying drawings, Figure 1 represents a front elevation of a device to which my improvements have been applied, located at a subscribers or out station. Fig. 2 represents a similar view of a device to which my improvements have been applied, located at the central or main station. Fig.3 is a detail view, partially in section, of the electrical contact-points of the central-station device; and Fig. 4, a diagram view, illustrating an open'circuit system connecting three subscribers with a central office, and shows my improvements applied thereto.

To enable others skilled in the art to make and use my invention, I will now proceed to describe it in detail, omitting a particular description of such parts of a telephone system as are well known or not necessary to a full understanding of my invention.

In the drawings the same letters of reference indicate the same parts.

A represents the central-station device. It comprises a clock mechanism or spring-impelled train of gears, B,the movement of which is normally arrested by an arm, a, keyed to a rotating arbor, d, of said mechanism engaging the stop-rod b, the spring 0 of which serving to keep the rod in engagement. The same arbor d, to which arm a is attached, carries a metallic revolving arm, 6, having a contactpiece, 0.

G represents ametallic plate insulated from the adjacent mechanism, except when a call is desired to be made. It is,however, connected electrically with the battery, magneto-machine, or other source of electrical energy. This plate 0 has secured to it a revolving contactarm, f, of the same radius as arm 6, and arranged concentrically thereto. arranged behind the plate 0 and adjacent to arm 0 of the clock mechanism, and is arranged, under certain conditions, to contact therewith in the manner shortly 'to be described.

Keyed upon the same pivotal point and in the same relative position as arm f is a needle, g, in front of plate 0 and upon dial h. A milled head, i, or other known device secured to their pivotal point admits of their being turned or adjusted by hand at the will of the operator. The normal position of arm eis that shown in dotted lines, Fig. 2.

The figures upon the dial it indicate the different points to which needle h and arm f shouldlie when it is desired to call a subscriber the number of whose station corresponds with its respective number on the dial-face.

1 The dial-face is here shown arranged for ten out stations or subscribers; but it is obvious that any desired number may be similarly arranged. t

The stop-rod b is secured to the frame of the clock mechanism B, and carries at its outer end a contact plate or point,j, and is so arranged as to momentarily contact the metalarm 7r, electrically connected with plate 0, whenever the stop-rod b is actuated.

This armfis The individual-call-alarm apparatus ofeach the armature I of an electro-magnet,'1. The

electro-magnet I is arranged within the mainline circuit, and is excited, causing it to attract its armature whenever the current flows over the line.

K is an electro-magnet, and is used as a letoff for the alarm bell, which is rung by the spring E for a set time. A wire, m, from the main line connects with said magnet, and the other end, a, is led to a spring contact-point, 0,where further electrical connection is broken, except when arm H is released from catch 1 through the action of armature I, and makes a revolution and is again arrested. In that event spring 0 is arranged to lie within the cir- .cular path of said arm H,.so that when arm H 7 clocks.

' allow it to freely rotate.

and spring 0 make momentary contact the circuit will be closed, (provided the current is at that moment on through the central station,) the current taking through arm H to frame D of trains of gears and out to main line through wire 19. This momentary closing of the circuit through magnet K causes armature K to be attracted,whereby the outer end or extension, K of said armature is made to strike lever L and release the alarm mechanism. This lever L, beyond its pivotal point, is bifurcated, the outer end of each bifurcation O and P being arranged to engage notched rotating disks of different diameters and rotated at differing rates ofspeed by reason oftheir being mounted upon different arbors. In the alarm-train of gears here shown the disk N is made to rotate about twelve times faster than disk M; but the disk M hastwo notches diametrically opposite, while disk N has but one.

Wheel Q of the alarm mechanism carries a series of equidistant studs, which cause the bell-lever R to vibrate in the usual wellknown way common to the striking mechanisms of When the lever L is struck by the extension K of armature K it raises both of its arms 0 P out of their respective notches in the disks N M. The-notches in disk M being deeper than the one in disk N, it follows that if the arm I, being in the bottom ofits notch, be lifted out so as to rest upon the circumference of said disk, it raises the arm 0 at the same time sufficiently high to clear disk N and The alarm mechanism continues to rotate till the succeeding notch in the disk M comes opposite arm P, when it will be received therein, thereby bringin g the arm 0 so that it will engage the notch indisk N and stop the mechanism.

The arm 0 and consequently arm P are prevented from rising too high, and also accelerated in their return to their normal position, or position within the notches, by the arm q, attached to and rotating with the fan 1", making abrushing-contact with arm 0. The force of gravity may be also employed for returning lever L to its normal position or any other suitable and known way.

The operation of my invention is as follows: In diagram Fig. 4 are shown a central station-,and three subscribers or out stations arranged within a circuit. I would here remark that each subscriber is provided with a magneto-call, switch, or other known device (not shown) for calling the central station, and a telephone. (Also not shown.) The central office is also provided with an annunciator or other alarm, and with any suitable and wellknown means for making electrical connection therewith, whereby a signal may be sent through the annunciator by any subscriber or out station.

In diagram Fig. 4 there are but three out stations. Therefore but three corresponding points, 1 2 3, are provided on the dial at the central station. 7 In Fig. 2, however, the central-station dial it is arranged for calling a series of ten out stations, of which the appara tus shown in Fig. 1 is represented to be out station No. 1, for the reason that the contact point or spring 0 of arm H is arranged within that portion of the circumferential path of arm H corresponding to point 1 on the dial of the central station traversed by arms 0 and f g.

In tracing out the lines of the current shown by diagram Fig. 4. reference should be made to the other figures of the drawings. I will confine myself to describing the means or manner in which the central-office operator calls any one of the several stations without ringing the alarm of any other than that one desired to be communicated with.

Normally the batterycurrent, or current from the magneto-machine, is broken at plate 0, and arm e is in the position shown in Figs. 2 and 4, out of contact. If, now, the operator desires to call station No.1, (see Fig. 4,) he first turns the needle 9, and consequently contact-armf, so as to lie in the direction of l on the dial of the central station, and which is also the direction of contact-spring 0 in station No. 1. The operator next momentarily depresses stop-rod b, when it regains its original position through spring 0. This operation has had the effect, first, of releasing arm a of the clock mechanism,allowing it to rotate arm-e audits contact 0, and, secondly, at the same time making electrical contact between plates j and and 7c momentarily. The result of this contact is that the current passes from the battery through plate 0, arm is, arm j, stop-rod I), through the conducting-frame of the clock mechanism, out to the line-wire which passes through the several subscribers stations to earth, thereby throwing upon the line a single momentary impulse. This impulse causes each electro-magnet I to attract its armature for a moment, after which it is demagnetized by arms In breaking their brief contact. Upon armature I being attracted, as above stated, it causes arm H of each station to be released, and they all revolve synchronously together, and also with arm 0 of the central office. Now, in Fig. 4 the needle 9 and its contact-arm f have been set to lie in the direction of the figure 1, corresponding to the position of springcontact 0 in out station No. 1. It follows that ifvthe arm 0 of the one and the arm H of the other are released at the same moment and revolved synchronously, they will both make electrical contact at the same time, the arm 0 with the arm f, and the arm H with the spring 0, when the current will pass through the electro-magnet K of station No. 1, and the letoff-alarm mechanism of that station be sounded in the manner before set forth.

It will be observed that the spring contactpoints 0 in each of the other subscribers stations are arranged in a different point in the circumferential path of the arm H Consequently no electrical contact took place when. electrical connection was made at station No. 1 and at the central station, as above stated. When, however, in the complete revolution which the arm H of each apparatus and arm 0 of the central station necessarily make before being again stopped, (the arm H by armature I and the arm 0 by stop-rod 1),) the arms H of stations No. 2 and 3 make contact with their respective springs 0, no current is generated,for the reason that electrical contact of arm 6 at the central station does not again ensue during that revolution of the arm, and consequently the battery-current is not during that time again thrown upon the line. In like manner, when station No. 2 is desired to be called, the needle 9 is set so as to lie in the direction of the figure 2 at the central station, and the stop-rod b is again momentarily depressed, when a similar result takes place as that described in connection with station No. 1. In like manner, also, station No. 3 is called. In stations No. 1 and 3 of Fig. 4, when arm H and spring 0 make electrical contact, the current flows out to the main wire; but in station No. 2, when such contact is made, the current is grounded by wire 1) being connected with the earth instead of with the line. Either or both of these methods may be used, or any other suitable and known method.

Instead of providing arm 0 of the central 0tfice with an indicator-needle, the indicatorneedle might be dispensed with, either by making the dial transparent and providing equivalent electrical connections for the parts or by any other suitable and desirable way.

It is obvious that my devices may be adapted easily [or use on closed circuits. It will be apparent, also, that as the current-is employed to simply release an alarm or bell mechanism, which is in itself rung by a spring-weight or equivalent, the alarm may be sounded as long and as loud as desired, depending merely upon the size and force of the alarm, and not upon the current flowing over the line. By these devices, also, it will be 'seen that a comparatively slight current may be successfully employed in this manner, and which does not require to be materially changed in order to adapt it for alarms ot large size and power or for a great number of outstations on the circuit. It is suitable for fire-alarm telegraphs, and may be used with good results for ringing the alarms of large clockssuch as public time-pieces for striking the hour. It is also easily adapted to a series of weight or spring impelled trains of gears, where they are adapted for doing a certain periodical work, each at its own time.

.Instead of the springs 0 in each of the subscribers stations being arranged in different relative positions, as described, the arms H might be arranged in that manner, and so as to be arrested each by its armature I, and the springs 0 each have the same relative position occupied by arms H.

I am aware that it is not new to constructa central or subscribers station with a clockwork, a revolving and stationary electrode, an electro-magnet for operating said clock, and a ma gneto-bell rung thereby, and such, therefore, I do not claim broadly; but

What I do claim is- 1. A clock mechanism normally at rest, an electro-magnet and armature arranged in the main -line circuit for controlling said clock mechanism, a main circuit, a branch or grounding circuit, two electrodes,one of which is arevolving arm and the other a stationary spring or point, an alarm mechanism consisting ot'a spring-impelled train of gears, as described, and an electro magnet and armature arranged in said branch or grounding circuit for releasing the self-impelled-alarm mechanism, all constructed to act in combination in the manner and for the purposes herein set forth.

2. A number of stations in a single electric circuit, each comprising a clock mechanism normally at rest, an electro-magnet and armature arranged in said circuit for controlling said clock mechanism, a branch or grounding circuit, two electrodes, one of which is a revolvin g arm and the other a stationary spring or point, an alarm mechanism consisting of a springimpelled train of gears, as described, and an electro-magnet and armature arranged in said branch or grounding circuit for releas' ing said alarm mechanism, the revolving armelectrode of each station being also normally at rest, so that when said electrodes are released by their respective electro-magnets by a single impulse generated upon the main line, they will each rotate synchronously for one revolution, during which they will close the circuit through their respective branch or ground wire, each at a difierent period of the revolu tion, thereby releasing their self impelled alarms through the electro-magnet and armature in the said branch circuit.

3. A clock mechanism at the central station normally at rest, a revolving electrode carried thereby, another electrodeadjustable by hand and arranged to contact the revolving electrode, as described, and a catch for holding said clock-work normally at rest, operated by IOC IIS

hand, and carrying a contact-point, whereby the battery-current will be thrown upon the line momentarily when the catch is operated, in combination with an out station or stations,

4 camera each comprising a clock mechanism, an electro-magnet and armature arranged in the main circuit forcontrolling said clock-work, abraneh or groundingcircuit, two electrodes, one of which is a revolving arm and the other a stationary spring or point, an alarm mechanism consisting of a spring-impelled train of gears, as described, and an electro-magnet and armature arranged in said branch or grounding circuit for releasing said alarm,the revolving electrodes of all the stations upon bein leased (the central station by its catch, and the out stations through their electro-niagnets and armature in the main line) by a single impulse generated upon the main line, they will each rotate synchronously for one revolution, during which that out station, and that only, whose stationary electrode lies in the same direction as that to which the adjustable electrode of the central station has been set will have its branch or ground-wire circuit closed and the armature and magnet therein attracted, thereby releasing the spring-impelled alarm.

4. A clock mechanism, a single ret'olving electrode carried thereby, acatch for holding said clock-work normally atrest, operated by hand, an electrode carried by said catch, an-

- other electrode connected with a battery, and

suitable wires arranged in an open circuit, all constructed to act in combination, whereby the clock-work'will be mechanically released, so that the revolving electrode will make one revolution and a single contact, and the other two electrodes electrically contacted, so as to send a single impulse through the line upon the catch being operated, substantially as set forth.

5. A clock mechanism, a revolving electrode carried thereby, another electrode adjustable by hand, and arranged to contact the revolving electrode, as described, a catch for holding said clock-work normally at rest, operated by hand, an electrode carried by said c'atch, another electrode connected with the battery, and suitable wires arranged in an open circuit, all constructed to act in combination, whereby the clock-work will be me chanieally released and the two last-named electrodes first electrically contacted, so as to send a, single impulse through the line upon the catch being operated, and thenthe revolving and adj ustable electrodes contacted, so as to send a second impulse through the line for the purposes described.

In testimony whereof Iaffix my signature in presence of two witnesses.

JAMES F; KETTELlh.

WVitnesses:

JONAS HEALD, JOHN J. UPIIAM. 

